
import * as Cesium from 'cesium'
const Cartesian2 = Cesium.Cartesian2
const Cartesian3 = Cesium.Cartesian3
const Cartographic = Cesium.Cartographic
const combine = Cesium.combine
const Credit = Cesium.Credit
const defaultValue = Cesium.defaultValue
const defined = Cesium.defined
const DeveloperError = Cesium.DeveloperError
const Event = Cesium.Event
const GeographicProjection = Cesium.GeographicProjection
const CesiumMath = Cesium.CesiumMath
const Rectangle = Cesium.Rectangle
const Resource = Cesium.Resource
const WebMercatorTilingScheme = Cesium.WebMercatorTilingScheme
const ImageryProvider = Cesium.ImageryProvider
const when = Cesium.when

let templateRegex = /{[^}]+}/g

let tags = {
  x: xTag,
  y: yTag,
  z: zTag,
  s: sTag,
  reverseX: reverseXTag,
  reverseY: reverseYTag,
  reverseZ: reverseZTag,
  westDegrees: westDegreesTag,
  southDegrees: southDegreesTag,
  eastDegrees: eastDegreesTag,
  northDegrees: northDegreesTag,
  westProjected: westProjectedTag,
  southProjected: southProjectedTag,
  eastProjected: eastProjectedTag,
  northProjected: northProjectedTag,
  width: widthTag,
  height: heightTag
}

let pickFeaturesTags = combine(tags, {
  i: iTag,
  j: jTag,
  reverseI: reverseITag,
  reverseJ: reverseJTag,
  longitudeDegrees: longitudeDegreesTag,
  latitudeDegrees: latitudeDegreesTag,
  longitudeProjected: longitudeProjectedTag,
  latitudeProjected: latitudeProjectedTag,
  format: formatTag
})

/**
 * @typedef {Object} UrlTemplateImageryProvider.ConstructorOptions
 *
 * Initialization options for the UrlTemplateImageryProvider constructor
 *
 * @property {Promise.<Object>|Object} [options] Object with the following properties:
 * @property {Resource|String} url  The URL template to use to request tiles.  It has the following keywords:
 * <ul>
 *     <li><code>{z}</code>: The level of the tile in the tiling scheme.  Level zero is the root of the quadtree pyramid.</li>
 *     <li><code>{x}</code>: The tile X coordinate in the tiling scheme, where 0 is the Westernmost tile.</li>
 *     <li><code>{y}</code>: The tile Y coordinate in the tiling scheme, where 0 is the Northernmost tile.</li>
 *     <li><code>{s}</code>: One of the available subdomains, used to overcome browser limits on the number of simultaneous requests per host.</li>
 *     <li><code>{reverseX}</code>: The tile X coordinate in the tiling scheme, where 0 is the Easternmost tile.</li>
 *     <li><code>{reverseY}</code>: The tile Y coordinate in the tiling scheme, where 0 is the Southernmost tile.</li>
 *     <li><code>{reverseZ}</code>: The level of the tile in the tiling scheme, where level zero is the maximum level of the quadtree pyramid.  In order to use reverseZ, maximumLevel must be defined.</li>
 *     <li><code>{westDegrees}</code>: The Western edge of the tile in geodetic degrees.</li>
 *     <li><code>{southDegrees}</code>: The Southern edge of the tile in geodetic degrees.</li>
 *     <li><code>{eastDegrees}</code>: The Eastern edge of the tile in geodetic degrees.</li>
 *     <li><code>{northDegrees}</code>: The Northern edge of the tile in geodetic degrees.</li>
 *     <li><code>{westProjected}</code>: The Western edge of the tile in projected coordinates of the tiling scheme.</li>
 *     <li><code>{southProjected}</code>: The Southern edge of the tile in projected coordinates of the tiling scheme.</li>
 *     <li><code>{eastProjected}</code>: The Eastern edge of the tile in projected coordinates of the tiling scheme.</li>
 *     <li><code>{northProjected}</code>: The Northern edge of the tile in projected coordinates of the tiling scheme.</li>
 *     <li><code>{width}</code>: The width of each tile in pixels.</li>
 *     <li><code>{height}</code>: The height of each tile in pixels.</li>
 * </ul>
 * @property {Resource|String} [pickFeaturesUrl] The URL template to use to pick features.  If this property is not specified,
 *                 {@link UrlTemplateImageryProvider#pickFeatures} will immediately returned undefined, indicating no
 *                 features picked.  The URL template supports all of the keywords supported by the <code>url</code>
 *                 parameter, plus the following:
 * <ul>
 *     <li><code>{i}</code>: The pixel column (horizontal coordinate) of the picked position, where the Westernmost pixel is 0.</li>
 *     <li><code>{j}</code>: The pixel row (vertical coordinate) of the picked position, where the Northernmost pixel is 0.</li>
 *     <li><code>{reverseI}</code>: The pixel column (horizontal coordinate) of the picked position, where the Easternmost pixel is 0.</li>
 *     <li><code>{reverseJ}</code>: The pixel row (vertical coordinate) of the picked position, where the Southernmost pixel is 0.</li>
 *     <li><code>{longitudeDegrees}</code>: The longitude of the picked position in degrees.</li>
 *     <li><code>{latitudeDegrees}</code>: The latitude of the picked position in degrees.</li>
 *     <li><code>{longitudeProjected}</code>: The longitude of the picked position in the projected coordinates of the tiling scheme.</li>
 *     <li><code>{latitudeProjected}</code>: The latitude of the picked position in the projected coordinates of the tiling scheme.</li>
 *     <li><code>{format}</code>: The format in which to get feature information, as specified in the {@link GetFeatureInfoFormat}.</li>
 * </ul>
 * @property {Object} [urlSchemeZeroPadding] Gets the URL scheme zero padding for each tile coordinate. The format is '000' where
 * each coordinate will be padded on the left with zeros to match the width of the passed string of zeros. e.g. Setting:
 * urlSchemeZeroPadding : { '{x}' : '0000'}
 * will cause an 'x' value of 12 to return the string '0012' for {x} in the generated URL.
 * It the passed object has the following keywords:
 * <ul>
 *  <li> <code>{z}</code>: The zero padding for the level of the tile in the tiling scheme.</li>
 *  <li> <code>{x}</code>: The zero padding for the tile X coordinate in the tiling scheme.</li>
 *  <li> <code>{y}</code>: The zero padding for the the tile Y coordinate in the tiling scheme.</li>
 *  <li> <code>{reverseX}</code>: The zero padding for the tile reverseX coordinate in the tiling scheme.</li>
 *  <li> <code>{reverseY}</code>: The zero padding for the tile reverseY coordinate in the tiling scheme.</li>
 *  <li> <code>{reverseZ}</code>: The zero padding for the reverseZ coordinate of the tile in the tiling scheme.</li>
 * </ul>
 * @property {String|String[]} [subdomains='abc'] The subdomains to use for the <code>{s}</code> placeholder in the URL template.
 *                          If this parameter is a single string, each character in the string is a subdomain.  If it is
 *                          an array, each element in the array is a subdomain.
 * @property {Credit|String} [credit=''] A credit for the data source, which is displayed on the canvas.
 * @property {Number} [minimumLevel=0] The minimum level-of-detail supported by the imagery provider.  Take care when specifying
 *                 this that the number of tiles at the minimum level is small, such as four or less.  A larger number is likely
 *                 to result in rendering problems.
 * @property {Number} [maximumLevel] The maximum level-of-detail supported by the imagery provider, or undefined if there is no limit.
 * @property {Rectangle} [rectangle=Rectangle.MAX_VALUE] The rectangle, in radians, covered by the image.
 * @property {TilingScheme} [tilingScheme=WebMercatorTilingScheme] The tiling scheme specifying how the ellipsoidal
 * surface is broken into tiles.  If this parameter is not provided, a {@link WebMercatorTilingScheme}
 * is used.
 * @property {Ellipsoid} [ellipsoid] The ellipsoid.  If the tilingScheme is specified,
 *                    this parameter is ignored and the tiling scheme's ellipsoid is used instead. If neither
 *                    parameter is specified, the WGS84 ellipsoid is used.
 * @property {Number} [tileWidth=256] Pixel width of image tiles.
 * @property {Number} [tileHeight=256] Pixel height of image tiles.
 * @property {Boolean} [hasAlphaChannel=true] true if the images provided by this imagery provider
 *                  include an alpha channel; otherwise, false.  If this property is false, an alpha channel, if
 *                  present, will be ignored.  If this property is true, any images without an alpha channel will
 *                  be treated as if their alpha is 1.0 everywhere.  When this property is false, memory usage
 *                  and texture upload time are potentially reduced.
 * @property {GetFeatureInfoFormat[]} [getFeatureInfoFormats] The formats in which to get feature information at a
 *                                 specific location when {@link UrlTemplateImageryProvider#pickFeatures} is invoked.  If this
 *                                 parameter is not specified, feature picking is disabled.
 * @property {Boolean} [enablePickFeatures=true] If true, {@link UrlTemplateImageryProvider#pickFeatures} will
 *        request the <code>pickFeaturesUrl</code> and attempt to interpret the features included in the response.  If false,
 *        {@link UrlTemplateImageryProvider#pickFeatures} will immediately return undefined (indicating no pickable
 *        features) without communicating with the server.  Set this property to false if you know your data
 *        source does not support picking features or if you don't want this provider's features to be pickable. Note
 *        that this can be dynamically overridden by modifying the {@link UriTemplateImageryProvider#enablePickFeatures}
 *        property.
 * @property {Object} [customTags] Allow to replace custom keywords in the URL template. The object must have strings as keys and functions as values.
 */

/**
 * Provides imagery by requesting tiles using a specified URL template.
 *
 * @alias UrlTemplateImageryProvider
 * @constructor
 *
 * @param {UrlTemplateImageryProvider.ConstructorOptions} options Object describing initialization options
 *
 * @example
 * // Access Natural Earth II imagery, which uses a TMS tiling scheme and Geographic (EPSG:4326) project
 * var tms = new Cesium.UrlTemplateImageryProvider({
 *     url : Cesium.buildModuleUrl('Assets/Textures/NaturalEarthII') + '/{z}/{x}/{reverseY}.jpg',
 *     credit : '© Analytical Graphics, Inc.',
 *     tilingScheme : new Cesium.GeographicTilingScheme(),
 *     maximumLevel : 5
 * });
 * // Access the CartoDB Positron basemap, which uses an OpenStreetMap-like tiling scheme.
 * var positron = new Cesium.UrlTemplateImageryProvider({
 *     url : 'http://{s}.basemaps.cartocdn.com/light_all/{z}/{x}/{y}.png',
 *     credit : 'Map tiles by CartoDB, under CC BY 3.0. Data by OpenStreetMap, under ODbL.'
 * });
 * // Access a Web Map Service (WMS) server.
 * var wms = new Cesium.UrlTemplateImageryProvider({
 *    url : 'https://programs.communications.gov.au/geoserver/ows?tiled=true&' +
 *          'transparent=true&format=image%2Fpng&exceptions=application%2Fvnd.ogc.se_xml&' +
 *          'styles=&service=WMS&version=1.1.1&request=GetMap&' +
 *          'layers=public%3AMyBroadband_Availability&srs=EPSG%3A3857&' +
 *          'bbox={westProjected}%2C{southProjected}%2C{eastProjected}%2C{northProjected}&' +
 *          'width=256&height=256',
 *    rectangle : Cesium.Rectangle.fromDegrees(96.799393, -43.598214999057824, 153.63925700000001, -9.2159219997013)
 * });
 * // Using custom tags in your template url.
 * var custom = new Cesium.UrlTemplateImageryProvider({
 *    url : 'https://yoururl/{Time}/{z}/{y}/{x}.png',
 *    customTags : {
 *        Time: function(imageryProvider, x, y, level) {
 *            return '20171231'
 *        }
 *    }
 * });
 *
 * @see ArcGisMapServerImageryProvider
 * @see BingMapsImageryProvider
 * @see GoogleEarthEnterpriseMapsProvider
 * @see OpenStreetMapImageryProvider
 * @see SingleTileImageryProvider
 * @see TileMapServiceImageryProvider
 * @see WebMapServiceImageryProvider
 * @see WebMapTileServiceImageryProvider
 */
function UrlTemplateImageryProvider (options) {
  // >>includeStart('debug', pragmas.debug);
  if (!defined(options)) {
    throw new DeveloperError('options is required.')
  }
  if (!when.isPromise(options) && !defined(options.url)) {
    throw new DeveloperError('options is required.')
  }
  // >>includeEnd('debug');

  this._errorEvent = new Event()

  this._resource = undefined
  this._urlSchemeZeroPadding = undefined
  this._pickFeaturesResource = undefined
  this._tileWidth = undefined
  this._tileHeight = undefined
  this._maximumLevel = undefined
  this._minimumLevel = undefined
  this._tilingScheme = undefined
  this._rectangle = undefined
  this._tileDiscardPolicy = undefined
  this._credit = undefined
  this._hasAlphaChannel = undefined
  this._readyPromise = undefined
  this._tags = undefined
  this._pickFeaturesTags = undefined

  /**
   * The default alpha blending value of this provider, with 0.0 representing fully transparent and
   * 1.0 representing fully opaque.
   *
   * @type {Number|undefined}
   * @default undefined
   */
  this.defaultAlpha = undefined

  /**
   * The default alpha blending value on the night side of the globe of this provider, with 0.0 representing fully transparent and
   * 1.0 representing fully opaque.
   *
   * @type {Number|undefined}
   * @default undefined
   */
  this.defaultNightAlpha = undefined

  /**
   * The default alpha blending value on the day side of the globe of this provider, with 0.0 representing fully transparent and
   * 1.0 representing fully opaque.
   *
   * @type {Number|undefined}
   * @default undefined
   */
  this.defaultDayAlpha = undefined

  /**
   * The default brightness of this provider.  1.0 uses the unmodified imagery color.  Less than 1.0
   * makes the imagery darker while greater than 1.0 makes it brighter.
   *
   * @type {Number|undefined}
   * @default undefined
   */
  this.defaultBrightness = undefined

  /**
   * The default contrast of this provider.  1.0 uses the unmodified imagery color.  Less than 1.0 reduces
   * the contrast while greater than 1.0 increases it.
   *
   * @type {Number|undefined}
   * @default undefined
   */
  this.defaultContrast = undefined

  /**
   * The default hue of this provider in radians. 0.0 uses the unmodified imagery color.
   *
   * @type {Number|undefined}
   * @default undefined
   */
  this.defaultHue = undefined

  /**
   * The default saturation of this provider. 1.0 uses the unmodified imagery color. Less than 1.0 reduces the
   * saturation while greater than 1.0 increases it.
   *
   * @type {Number|undefined}
   * @default undefined
   */
  this.defaultSaturation = undefined

  /**
   * The default gamma correction to apply to this provider.  1.0 uses the unmodified imagery color.
   *
   * @type {Number|undefined}
   * @default undefined
   */
  this.defaultGamma = undefined

  /**
   * The default texture minification filter to apply to this provider.
   *
   * @type {TextureMinificationFilter}
   * @default undefined
   */
  this.defaultMinificationFilter = undefined

  /**
   * The default texture magnification filter to apply to this provider.
   *
   * @type {TextureMagnificationFilter}
   * @default undefined
   */
  this.defaultMagnificationFilter = undefined

  /**
   * Gets or sets a value indicating whether feature picking is enabled.  If true, {@link UrlTemplateImageryProvider#pickFeatures} will
   * request the <code>options.pickFeaturesUrl</code> and attempt to interpret the features included in the response.  If false,
   * {@link UrlTemplateImageryProvider#pickFeatures} will immediately return undefined (indicating no pickable
   * features) without communicating with the server.  Set this property to false if you know your data
   * source does not support picking features or if you don't want this provider's features to be pickable.
   * @type {Boolean}
   * @default true
   */
  this.enablePickFeatures = true

  this.reinitialize(options)
}

Object.defineProperties(UrlTemplateImageryProvider.prototype, {
  /**
   * Gets the URL template to use to request tiles.  It has the following keywords:
   * <ul>
   *  <li> <code>{z}</code>: The level of the tile in the tiling scheme.  Level zero is the root of the quadtree pyramid.</li>
   *  <li> <code>{x}</code>: The tile X coordinate in the tiling scheme, where 0 is the Westernmost tile.</li>
   *  <li> <code>{y}</code>: The tile Y coordinate in the tiling scheme, where 0 is the Northernmost tile.</li>
   *  <li> <code>{s}</code>: One of the available subdomains, used to overcome browser limits on the number of simultaneous requests per host.</li>
   *  <li> <code>{reverseX}</code>: The tile X coordinate in the tiling scheme, where 0 is the Easternmost tile.</li>
   *  <li> <code>{reverseY}</code>: The tile Y coordinate in the tiling scheme, where 0 is the Southernmost tile.</li>
   *  <li> <code>{reverseZ}</code>: The level of the tile in the tiling scheme, where level zero is the maximum level of the quadtree pyramid.  In order to use reverseZ, maximumLevel must be defined.</li>
   *  <li> <code>{westDegrees}</code>: The Western edge of the tile in geodetic degrees.</li>
   *  <li> <code>{southDegrees}</code>: The Southern edge of the tile in geodetic degrees.</li>
   *  <li> <code>{eastDegrees}</code>: The Eastern edge of the tile in geodetic degrees.</li>
   *  <li> <code>{northDegrees}</code>: The Northern edge of the tile in geodetic degrees.</li>
   *  <li> <code>{westProjected}</code>: The Western edge of the tile in projected coordinates of the tiling scheme.</li>
   *  <li> <code>{southProjected}</code>: The Southern edge of the tile in projected coordinates of the tiling scheme.</li>
   *  <li> <code>{eastProjected}</code>: The Eastern edge of the tile in projected coordinates of the tiling scheme.</li>
   *  <li> <code>{northProjected}</code>: The Northern edge of the tile in projected coordinates of the tiling scheme.</li>
   *  <li> <code>{width}</code>: The width of each tile in pixels.</li>
   *  <li> <code>{height}</code>: The height of each tile in pixels.</li>
   * </ul>
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {String}
   * @readonly
   */
  url: {
    get: function () {
      return this._resource.url
    }
  },

  /**
   * Gets the URL scheme zero padding for each tile coordinate. The format is '000' where each coordinate will be padded on
   * the left with zeros to match the width of the passed string of zeros. e.g. Setting:
   * urlSchemeZeroPadding : { '{x}' : '0000'}
   * will cause an 'x' value of 12 to return the string '0012' for {x} in the generated URL.
   * It has the following keywords:
   * <ul>
   *  <li> <code>{z}</code>: The zero padding for the level of the tile in the tiling scheme.</li>
   *  <li> <code>{x}</code>: The zero padding for the tile X coordinate in the tiling scheme.</li>
   *  <li> <code>{y}</code>: The zero padding for the the tile Y coordinate in the tiling scheme.</li>
   *  <li> <code>{reverseX}</code>: The zero padding for the tile reverseX coordinate in the tiling scheme.</li>
   *  <li> <code>{reverseY}</code>: The zero padding for the tile reverseY coordinate in the tiling scheme.</li>
   *  <li> <code>{reverseZ}</code>: The zero padding for the reverseZ coordinate of the tile in the tiling scheme.</li>
   * </ul>
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Object}
   * @readonly
   */
  urlSchemeZeroPadding: {
    get: function () {
      return this._urlSchemeZeroPadding
    }
  },

  /**
   * Gets the URL template to use to use to pick features.  If this property is not specified,
   * {@link UrlTemplateImageryProvider#pickFeatures} will immediately return undefined, indicating no
   * features picked.  The URL template supports all of the keywords supported by the
   * {@link UrlTemplateImageryProvider#url} property, plus the following:
   * <ul>
   *     <li><code>{i}</code>: The pixel column (horizontal coordinate) of the picked position, where the Westernmost pixel is 0.</li>
   *     <li><code>{j}</code>: The pixel row (vertical coordinate) of the picked position, where the Northernmost pixel is 0.</li>
   *     <li><code>{reverseI}</code>: The pixel column (horizontal coordinate) of the picked position, where the Easternmost pixel is 0.</li>
   *     <li><code>{reverseJ}</code>: The pixel row (vertical coordinate) of the picked position, where the Southernmost pixel is 0.</li>
   *     <li><code>{longitudeDegrees}</code>: The longitude of the picked position in degrees.</li>
   *     <li><code>{latitudeDegrees}</code>: The latitude of the picked position in degrees.</li>
   *     <li><code>{longitudeProjected}</code>: The longitude of the picked position in the projected coordinates of the tiling scheme.</li>
   *     <li><code>{latitudeProjected}</code>: The latitude of the picked position in the projected coordinates of the tiling scheme.</li>
   *     <li><code>{format}</code>: The format in which to get feature information, as specified in the {@link GetFeatureInfoFormat}.</li>
   * </ul>
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {String}
   * @readonly
   */
  pickFeaturesUrl: {
    get: function () {
      return this._pickFeaturesResource.url
    }
  },

  /**
   * Gets the proxy used by this provider.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Proxy}
   * @readonly
   * @default undefined
   */
  proxy: {
    get: function () {
      return this._resource.proxy
    }
  },

  /**
   * Gets the width of each tile, in pixels. This function should
   * not be called before {@link UrlTemplateImageryProvider#ready} returns true.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Number}
   * @readonly
   * @default 256
   */
  tileWidth: {
    get: function () {
      // >>includeStart('debug', pragmas.debug);
      if (!this.ready) {
        throw new DeveloperError(
          'tileWidth must not be called before the imagery provider is ready.'
        )
      }
      // >>includeEnd('debug');
      return this._tileWidth
    }
  },

  /**
   * Gets the height of each tile, in pixels.  This function should
   * not be called before {@link UrlTemplateImageryProvider#ready} returns true.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Number}
   * @readonly
   * @default 256
   */
  tileHeight: {
    get: function () {
      // >>includeStart('debug', pragmas.debug);
      if (!this.ready) {
        throw new DeveloperError(
          'tileHeight must not be called before the imagery provider is ready.'
        )
      }
      // >>includeEnd('debug');
      return this._tileHeight
    }
  },

  /**
   * Gets the maximum level-of-detail that can be requested, or undefined if there is no limit.
   * This function should not be called before {@link UrlTemplateImageryProvider#ready} returns true.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Number|undefined}
   * @readonly
   * @default undefined
   */
  maximumLevel: {
    get: function () {
      // >>includeStart('debug', pragmas.debug);
      if (!this.ready) {
        throw new DeveloperError(
          'maximumLevel must not be called before the imagery provider is ready.'
        )
      }
      // >>includeEnd('debug');
      return this._maximumLevel
    }
  },

  /**
   * Gets the minimum level-of-detail that can be requested.  This function should
   * not be called before {@link UrlTemplateImageryProvider#ready} returns true.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Number}
   * @readonly
   * @default 0
   */
  minimumLevel: {
    get: function () {
      // >>includeStart('debug', pragmas.debug);
      if (!this.ready) {
        throw new DeveloperError(
          'minimumLevel must not be called before the imagery provider is ready.'
        )
      }
      // >>includeEnd('debug');
      return this._minimumLevel
    }
  },

  /**
   * Gets the tiling scheme used by this provider.  This function should
   * not be called before {@link UrlTemplateImageryProvider#ready} returns true.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {TilingScheme}
   * @readonly
   * @default new WebMercatorTilingScheme()
   */
  tilingScheme: {
    get: function () {
      // >>includeStart('debug', pragmas.debug);
      if (!this.ready) {
        throw new DeveloperError(
          'tilingScheme must not be called before the imagery provider is ready.'
        )
      }
      // >>includeEnd('debug');
      return this._tilingScheme
    }
  },

  /**
   * Gets the rectangle, in radians, of the imagery provided by this instance.  This function should
   * not be called before {@link UrlTemplateImageryProvider#ready} returns true.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Rectangle}
   * @readonly
   * @default tilingScheme.rectangle
   */
  rectangle: {
    get: function () {
      // >>includeStart('debug', pragmas.debug);
      if (!this.ready) {
        throw new DeveloperError(
          'rectangle must not be called before the imagery provider is ready.'
        )
      }
      // >>includeEnd('debug');
      return this._rectangle
    }
  },

  /**
   * Gets the tile discard policy.  If not undefined, the discard policy is responsible
   * for filtering out "missing" tiles via its shouldDiscardImage function.  If this function
   * returns undefined, no tiles are filtered.  This function should
   * not be called before {@link UrlTemplateImageryProvider#ready} returns true.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {TileDiscardPolicy}
   * @readonly
   * @default undefined
   */
  tileDiscardPolicy: {
    get: function () {
      // >>includeStart('debug', pragmas.debug);
      if (!this.ready) {
        throw new DeveloperError(
          'tileDiscardPolicy must not be called before the imagery provider is ready.'
        )
      }
      // >>includeEnd('debug');
      return this._tileDiscardPolicy
    }
  },

  /**
   * Gets an event that is raised when the imagery provider encounters an asynchronous error.  By subscribing
   * to the event, you will be notified of the error and can potentially recover from it.  Event listeners
   * are passed an instance of {@link TileProviderError}.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Event}
   * @readonly
   */
  errorEvent: {
    get: function () {
      return this._errorEvent
    }
  },

  /**
   * Gets a value indicating whether or not the provider is ready for use.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Boolean}
   * @readonly
   */
  ready: {
    get: function () {
      return defined(this._resource)
    }
  },

  /**
   * Gets a promise that resolves to true when the provider is ready for use.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Promise.<Boolean>}
   * @readonly
   */
  readyPromise: {
    get: function () {
      return this._readyPromise
    }
  },

  /**
   * Gets the credit to display when this imagery provider is active.  Typically this is used to credit
   * the source of the imagery.  This function should not be called before {@link UrlTemplateImageryProvider#ready} returns true.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Credit}
   * @readonly
   * @default undefined
   */
  credit: {
    get: function () {
      // >>includeStart('debug', pragmas.debug);
      if (!this.ready) {
        throw new DeveloperError(
          'credit must not be called before the imagery provider is ready.'
        )
      }
      // >>includeEnd('debug');
      return this._credit
    }
  },

  /**
   * Gets a value indicating whether or not the images provided by this imagery provider
   * include an alpha channel.  If this property is false, an alpha channel, if present, will
   * be ignored.  If this property is true, any images without an alpha channel will be treated
   * as if their alpha is 1.0 everywhere.  When this property is false, memory usage
   * and texture upload time are reduced.  This function should
   * not be called before {@link ImageryProvider#ready} returns true.
   * @memberof UrlTemplateImageryProvider.prototype
   * @type {Boolean}
   * @readonly
   * @default true
   */
  hasAlphaChannel: {
    get: function () {
      // >>includeStart('debug', pragmas.debug);
      if (!this.ready) {
        throw new DeveloperError(
          'hasAlphaChannel must not be called before the imagery provider is ready.'
        )
      }
      // >>includeEnd('debug');
      return this._hasAlphaChannel
    }
  }
})

/**
 * Reinitializes this instance.  Reinitializing an instance already in use is supported, but it is not
 * recommended because existing tiles provided by the imagery provider will not be updated.
 *
 * @param {Promise.<Object>|Object} options Any of the options that may be passed to the {@link UrlTemplateImageryProvider} constructor.
 */
UrlTemplateImageryProvider.prototype.reinitialize = function (options) {
  let that = this
  that._readyPromise = when(options).then(function (properties) {
    // >>includeStart('debug', pragmas.debug);
    if (!defined(properties)) {
      throw new DeveloperError('options is required.')
    }
    if (!defined(properties.url)) {
      throw new DeveloperError('options.url is required.')
    }
    // >>includeEnd('debug');

    let customTags = properties.customTags
    let allTags = combine(tags, customTags)
    let allPickFeaturesTags = combine(pickFeaturesTags, customTags)
    let resource = Resource.createIfNeeded(properties.url)
    let pickFeaturesResource = Resource.createIfNeeded(
      properties.pickFeaturesUrl
    )

    that.enablePickFeatures = defaultValue(
      properties.enablePickFeatures,
      that.enablePickFeatures
    )
    that._urlSchemeZeroPadding = defaultValue(
      properties.urlSchemeZeroPadding,
      that.urlSchemeZeroPadding
    )
    that._tileDiscardPolicy = properties.tileDiscardPolicy
    that._getFeatureInfoFormats = properties.getFeatureInfoFormats

    that._subdomains = properties.subdomains
    if (Array.isArray(that._subdomains)) {
      that._subdomains = that._subdomains.slice()
    } else if (defined(that._subdomains) && that._subdomains.length > 0) {
      that._subdomains = that._subdomains.split('')
    } else {
      that._subdomains = ['a', 'b', 'c']
    }

    that._tileWidth = defaultValue(properties.tileWidth, 256)
    that._tileHeight = defaultValue(properties.tileHeight, 256)
    that._minimumLevel = defaultValue(properties.minimumLevel, 0)
    that._maximumLevel = properties.maximumLevel
    that._tilingScheme = defaultValue(
      properties.tilingScheme,
      new WebMercatorTilingScheme({ ellipsoid: properties.ellipsoid })
    )
    that._rectangle = defaultValue(
      properties.rectangle,
      that._tilingScheme.rectangle
    )
    that._rectangle = Rectangle.intersection(
      that._rectangle,
      that._tilingScheme.rectangle
    )
    that._hasAlphaChannel = defaultValue(properties.hasAlphaChannel, true)

    let credit = properties.credit
    if (typeof credit === 'string') {
      credit = new Credit(credit)
    }
    that._credit = credit

    that._resource = resource
    that._tags = allTags
    that._pickFeaturesResource = pickFeaturesResource
    that._pickFeaturesTags = allPickFeaturesTags

    return true
  })
}

/**
 * Gets the credits to be displayed when a given tile is displayed.
 *
 * @param {Number} x The tile X coordinate.
 * @param {Number} y The tile Y coordinate.
 * @param {Number} level The tile level;
 * @returns {Credit[]} The credits to be displayed when the tile is displayed.
 *
 * @exception {DeveloperError} <code>getTileCredits</code> must not be called before the imagery provider is ready.
 */
UrlTemplateImageryProvider.prototype.getTileCredits = function (x, y, level) {
  // >>includeStart('debug', pragmas.debug);
  if (!this.ready) {
    throw new DeveloperError(
      'getTileCredits must not be called before the imagery provider is ready.'
    )
  }
  // >>includeEnd('debug');
  return undefined
}

/**
 * Requests the image for a given tile.  This function should
 * not be called before {@link UrlTemplateImageryProvider#ready} returns true.
 *
 * @param {Number} x The tile X coordinate.
 * @param {Number} y The tile Y coordinate.
 * @param {Number} level The tile level.
 * @param {Request} [request] The request object. Intended for internal use only.
 * @returns {Promise.<HTMLImageElement|HTMLCanvasElement>|undefined} A promise for the image that will resolve when the image is available, or
 *          undefined if there are too many active requests to the server, and the request
 *          should be retried later.  The resolved image may be either an
 *          Image or a Canvas DOM object.
 */
UrlTemplateImageryProvider.prototype.requestImage = function (
  x,
  y,
  level,
  request
) {
  // >>includeStart('debug', pragmas.debug);
  if (!this.ready) {
    throw new DeveloperError(
      'requestImage must not be called before the imagery provider is ready.'
    )
  }
  // >>includeEnd('debug');
  return ImageryProvider.loadImage(
    this,
    buildImageResource(this, x, y, level + 1, request)
  )
}

/**
 * Asynchronously determines what features, if any, are located at a given longitude and latitude within
 * a tile.  This function should not be called before {@link ImageryProvider#ready} returns true.
 *
 * @param {Number} x The tile X coordinate.
 * @param {Number} y The tile Y coordinate.
 * @param {Number} level The tile level.
 * @param {Number} longitude The longitude at which to pick features.
 * @param {Number} latitude  The latitude at which to pick features.
 * @return {Promise.<ImageryLayerFeatureInfo[]>|undefined} A promise for the picked features that will resolve when the asynchronous
 *                   picking completes.  The resolved value is an array of {@link ImageryLayerFeatureInfo}
 *                   instances.  The array may be empty if no features are found at the given location.
 *                   It may also be undefined if picking is not supported.
 */
UrlTemplateImageryProvider.prototype.pickFeatures = function (
  x,
  y,
  level,
  longitude,
  latitude
) {
  // >>includeStart('debug', pragmas.debug);
  if (!this.ready) {
    throw new DeveloperError(
      'pickFeatures must not be called before the imagery provider is ready.'
    )
  }
  // >>includeEnd('debug');

  if (
    !this.enablePickFeatures ||
    !defined(this._pickFeaturesResource) ||
    this._getFeatureInfoFormats.length === 0
  ) {
    return undefined
  }

  let formatIndex = 0

  let that = this

  function handleResponse (format, data) {
    return format.callback(data)
  }

  function doRequest () {
    if (formatIndex >= that._getFeatureInfoFormats.length) {
      // No valid formats, so no features picked.
      return when([])
    }

    let format = that._getFeatureInfoFormats[formatIndex]
    let resource = buildPickFeaturesResource(
      that,
      x,
      y,
      level,
      longitude,
      latitude,
      format.format
    )

    ++formatIndex

    if (format.type === 'json') {
      return resource.fetchJson().then(format.callback).otherwise(doRequest)
    } else if (format.type === 'xml') {
      return resource.fetchXML().then(format.callback).otherwise(doRequest)
    } else if (format.type === 'text' || format.type === 'html') {
      return resource.fetchText().then(format.callback).otherwise(doRequest)
    }
    return resource
      .fetch({
        responseType: format.format
      })
      .then(handleResponse.bind(undefined, format))
      .otherwise(doRequest)
  }

  return doRequest()
}

let degreesScratchComputed = false
let degreesScratch = new Rectangle()
let projectedScratchComputed = false
let projectedScratch = new Rectangle()

function buildImageResource (imageryProvider, x, y, level, request) {
  degreesScratchComputed = false
  projectedScratchComputed = false

  let resource = imageryProvider._resource
  let url = resource.getUrlComponent(true)
  let allTags = imageryProvider._tags
  let templateValues = {}

  let match = url.match(templateRegex)
  if (defined(match)) {
    match.forEach(function (tag) {
      let key = tag.substring(1, tag.length - 1) // strip {}
      if (defined(allTags[key])) {
        templateValues[key] = allTags[key](imageryProvider, x, y, level)
      }
    })
  }

  return resource.getDerivedResource({
    request: request,
    templateValues: templateValues
  })
}

let ijScratchComputed = false
let ijScratch = new Cartesian2()
let longitudeLatitudeProjectedScratchComputed = false

function buildPickFeaturesResource (
  imageryProvider,
  x,
  y,
  level,
  longitude,
  latitude,
  format
) {
  degreesScratchComputed = false
  projectedScratchComputed = false
  ijScratchComputed = false
  longitudeLatitudeProjectedScratchComputed = false

  let resource = imageryProvider._pickFeaturesResource
  let url = resource.getUrlComponent(true)
  let allTags = imageryProvider._pickFeaturesTags
  let templateValues = {}
  let match = url.match(templateRegex)
  if (defined(match)) {
    match.forEach(function (tag) {
      let key = tag.substring(1, tag.length - 1) // strip {}
      if (defined(allTags[key])) {
        templateValues[key] = allTags[key](
          imageryProvider,
          x,
          y,
          level,
          longitude,
          latitude,
          format
        )
      }
    })
  }

  return resource.getDerivedResource({
    templateValues: templateValues
  })
}

function padWithZerosIfNecessary (imageryProvider, key, value) {
  if (
    imageryProvider &&
    imageryProvider.urlSchemeZeroPadding &&
    imageryProvider.urlSchemeZeroPadding.hasOwnProperty(key)
  ) {
    let paddingTemplate = imageryProvider.urlSchemeZeroPadding[key]
    if (typeof paddingTemplate === 'string') {
      let paddingTemplateWidth = paddingTemplate.length
      if (paddingTemplateWidth > 1) {
        value =
          value.length >= paddingTemplateWidth
            ? value
            : new Array(
              paddingTemplateWidth - value.toString().length + 1
            ).join('0') + value
      }
    }
  }
  return value
}

function xTag (imageryProvider, x, y, level) {
  return padWithZerosIfNecessary(imageryProvider, '{x}', x)
}

function reverseXTag (imageryProvider, x, y, level) {
  let reverseX =
    imageryProvider.tilingScheme.getNumberOfXTilesAtLevel(level) - x - 1
  return padWithZerosIfNecessary(imageryProvider, '{reverseX}', reverseX)
}

function yTag (imageryProvider, x, y, level) {
  return padWithZerosIfNecessary(imageryProvider, '{y}', y)
}

function reverseYTag (imageryProvider, x, y, level) {
  let reverseY =
    imageryProvider.tilingScheme.getNumberOfYTilesAtLevel(level) - y - 1
  return padWithZerosIfNecessary(imageryProvider, '{reverseY}', reverseY)
}

function reverseZTag (imageryProvider, x, y, level) {
  let maximumLevel = imageryProvider.maximumLevel
  let reverseZ =
    defined(maximumLevel) && level < maximumLevel
      ? maximumLevel - level - 1
      : level
  return padWithZerosIfNecessary(imageryProvider, '{reverseZ}', reverseZ)
}

function zTag (imageryProvider, x, y, level) {
  return padWithZerosIfNecessary(imageryProvider, '{z}', level)
}

function sTag (imageryProvider, x, y, level) {
  let index = (x + y + level) % imageryProvider._subdomains.length
  return imageryProvider._subdomains[index]
}

function computeDegrees (imageryProvider, x, y, level) {
  if (degreesScratchComputed) {
    return
  }

  imageryProvider.tilingScheme.tileXYToRectangle(x, y, level, degreesScratch)
  degreesScratch.west = CesiumMath.toDegrees(degreesScratch.west)
  degreesScratch.south = CesiumMath.toDegrees(degreesScratch.south)
  degreesScratch.east = CesiumMath.toDegrees(degreesScratch.east)
  degreesScratch.north = CesiumMath.toDegrees(degreesScratch.north)

  degreesScratchComputed = true
}

function westDegreesTag (imageryProvider, x, y, level) {
  computeDegrees(imageryProvider, x, y, level)
  return degreesScratch.west
}

function southDegreesTag (imageryProvider, x, y, level) {
  computeDegrees(imageryProvider, x, y, level)
  return degreesScratch.south
}

function eastDegreesTag (imageryProvider, x, y, level) {
  computeDegrees(imageryProvider, x, y, level)
  return degreesScratch.east
}

function northDegreesTag (imageryProvider, x, y, level) {
  computeDegrees(imageryProvider, x, y, level)
  return degreesScratch.north
}

function computeProjected (imageryProvider, x, y, level) {
  if (projectedScratchComputed) {
    return
  }

  imageryProvider.tilingScheme.tileXYToNativeRectangle(
    x,
    y,
    level,
    projectedScratch
  )

  projectedScratchComputed = true
}

function westProjectedTag (imageryProvider, x, y, level) {
  computeProjected(imageryProvider, x, y, level)
  return projectedScratch.west
}

function southProjectedTag (imageryProvider, x, y, level) {
  computeProjected(imageryProvider, x, y, level)
  return projectedScratch.south
}

function eastProjectedTag (imageryProvider, x, y, level) {
  computeProjected(imageryProvider, x, y, level)
  return projectedScratch.east
}

function northProjectedTag (imageryProvider, x, y, level) {
  computeProjected(imageryProvider, x, y, level)
  return projectedScratch.north
}

function widthTag (imageryProvider, x, y, level) {
  return imageryProvider.tileWidth
}

function heightTag (imageryProvider, x, y, level) {
  return imageryProvider.tileHeight
}

function iTag (imageryProvider, x, y, level, longitude, latitude, format) {
  computeIJ(imageryProvider, x, y, level, longitude, latitude)
  return ijScratch.x
}

function jTag (imageryProvider, x, y, level, longitude, latitude, format) {
  computeIJ(imageryProvider, x, y, level, longitude, latitude)
  return ijScratch.y
}

function reverseITag (
  imageryProvider,
  x,
  y,
  level,
  longitude,
  latitude,
  format
) {
  computeIJ(imageryProvider, x, y, level, longitude, latitude)
  return imageryProvider.tileWidth - ijScratch.x - 1
}

function reverseJTag (
  imageryProvider,
  x,
  y,
  level,
  longitude,
  latitude,
  format
) {
  computeIJ(imageryProvider, x, y, level, longitude, latitude)
  return imageryProvider.tileHeight - ijScratch.y - 1
}

let rectangleScratch = new Rectangle()
let longitudeLatitudeProjectedScratch = new Cartesian3()

function computeIJ (imageryProvider, x, y, level, longitude, latitude, format) {
  if (ijScratchComputed) {
    return
  }

  computeLongitudeLatitudeProjected(
    imageryProvider,
    x,
    y,
    level,
    longitude,
    latitude
  )
  let projected = longitudeLatitudeProjectedScratch

  let rectangle = imageryProvider.tilingScheme.tileXYToNativeRectangle(
    x,
    y,
    level,
    rectangleScratch
  )
  ijScratch.x =
    ((imageryProvider.tileWidth * (projected.x - rectangle.west)) /
      rectangle.width) |
    0
  ijScratch.y =
    ((imageryProvider.tileHeight * (rectangle.north - projected.y)) /
      rectangle.height) |
    0
  ijScratchComputed = true
}

function longitudeDegreesTag (
  imageryProvider,
  x,
  y,
  level,
  longitude,
  latitude,
  format
) {
  return CesiumMath.toDegrees(longitude)
}

function latitudeDegreesTag (
  imageryProvider,
  x,
  y,
  level,
  longitude,
  latitude,
  format
) {
  return CesiumMath.toDegrees(latitude)
}

function longitudeProjectedTag (
  imageryProvider,
  x,
  y,
  level,
  longitude,
  latitude,
  format
) {
  computeLongitudeLatitudeProjected(
    imageryProvider,
    x,
    y,
    level,
    longitude,
    latitude
  )
  return longitudeLatitudeProjectedScratch.x
}

function latitudeProjectedTag (
  imageryProvider,
  x,
  y,
  level,
  longitude,
  latitude,
  format
) {
  computeLongitudeLatitudeProjected(
    imageryProvider,
    x,
    y,
    level,
    longitude,
    latitude
  )
  return longitudeLatitudeProjectedScratch.y
}

let cartographicScratch = new Cartographic()

function computeLongitudeLatitudeProjected (
  imageryProvider,
  x,
  y,
  level,
  longitude,
  latitude,
  format
) {
  if (longitudeLatitudeProjectedScratchComputed) {
    return
  }

  if (imageryProvider.tilingScheme.projection instanceof GeographicProjection) {
    longitudeLatitudeProjectedScratch.x = CesiumMath.toDegrees(longitude)
    longitudeLatitudeProjectedScratch.y = CesiumMath.toDegrees(latitude)
  } else {
    let cartographic = cartographicScratch
    cartographic.longitude = longitude
    cartographic.latitude = latitude
    imageryProvider.tilingScheme.projection.project(
      cartographic,
      longitudeLatitudeProjectedScratch
    )
  }

  longitudeLatitudeProjectedScratchComputed = true
}

function formatTag (imageryProvider, x, y, level, longitude, latitude, format) {
  return format
}
export default UrlTemplateImageryProvider
